At age 36, Agatha Christie vanishes for eleven days, returning with no memory of the missing period. Decades later, a letter signed “R” forces her to confront the truth she has avoided, triggering a journey back into fractured memories, unfinished manuscripts, and the figure of Roy, a seductive alter ego born from resentment and despair. As Agatha revisits the nightmarish maze of her disappearance, reality and fiction overlap, revealing that the mystery she must solve is herself. The musical frames the story like a locked-room detective novel, but its core is psychological rather than criminal.